The American Civil Liberties Union urged a southwest Kansas school district Friday to call off plans for a pro-creationism group to talk to students about dinosaurs.

The Kansas and Western Missouri chapter of the ACLU and the organization's Program on Freedom of Religion and Belief raised concerns in an email that the assemblies will be used to "spread creationism" in the 1,100-student Hugoton district. Superintendent Mark Crawford said he isn't canceling the assemblies.

The issue arose because members of the Oklahoma-based Creation Truth Foundation are to speak next week at several events on school property, including public gatherings in the evening and assemblies during the school day.

Foundation instructor Matt Miles said creationism would be discussed only during events conducted outside the school day. During the school assemblies, students are shown pictures and fossils, Miles said.

"We're going to come in and talk about dinosaurs, so nothing Biblical," Miles said.

Crawford said the speakers, who also operate under the name of the Foundation for the Advancement of Childhood Education, won't be allowed to use the school assemblies to promote the evening events.

"I agree with the ACLU, in that, if a mandatory all-school assembly where creationist truths or creationist beliefs were expressed, that would be inappropriate public-school content, and that is not the case," Crawford said. "It's completely and totally school appropriate."

But Doug Bonney, legal director for the American Civil Liberties Union of Kansas and Western Missouri, said the chance for constitutional violations is high "because their whole evangelical reason for being is to promote Biblical creationism." He noted that the Creation Truth Foundation promotes the position that "dinosaurs were created on the sixth day by God and that dinosaurs were created to benefit Adam and Eve and walked on the earth with humans." The ACLU said the U.S. Supreme Court and the lower federal courts have consistently held that teaching or otherwise promoting creationism is unconstitutional.

"You could conjecture all you want that they will dumb it down or they will remove their Biblical creationism," Bonney said. "I doubt it. I think it will be impossible to do in a constitutional way."

The Creation Truth Foundation said on its website that the research of its founder, G. Thomas Sharp, revealed that "Darwinian evolutionism has overthrown, in the name of science, the dominance of the Bible (creation in particular) as the foundation of America's world view."

"America's only hope, it was determined, was for the Bible believing public of our land to awaken to the reality of a true Biblical faith," the site continued. "Basic to this renewal is a return to all of realities of Biblical Creation."

Besides speaking engagements, the foundation sells a science curriculum that it markets primarily to private Christian schools and home-schooled students.